From: Jakub Sitnicki <jakub@cloudflare.com>
Date: Mon, 25 May 2020 14:29:28 +0200
Subject: bpf: Fix returned error sign when link doesn't support updates
Patch-mainline: v5.8-rc1
Git-commit: fe537393b5795ecbe5746eec0e16124bc998a594
References: bsc#1177028

System calls encode returned errors as negative values. Fix a typo that
breaks this convention for bpf(LINK_UPDATE) when bpf_link doesn't support
update operation.

Fixes: f9d041271cf4 ("bpf: Refactor bpf_link update handling")
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200525122928.1164495-1-jakub@cloudflare.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Gary Lin <glin@suse.com>
---
 kernel/bpf/syscall.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -3661,7 +3661,7 @@ static int link_update(union bpf_attr *a
 	if (link->ops->update_prog)
 		ret = link->ops->update_prog(link, new_prog, old_prog);
 	else
-		ret = EINVAL;
+		ret = -EINVAL;
 
 out_put_progs:
 	if (old_prog)